Rapid and easy molecular authentication of medicinal plant Zingiber officinale Roscoe by loop-mediated isothermal amplification (LAMP)-based marker

The Zingiber genus, which includes the herbs known as gingers with maximal therapeutic properties, is well known for its medicinal importance as a purificant of body. Some morphological similar members of the genus are available but differ in their pharmacological and therapeutic properties. So there is an existing demand in herbal drug industry for an authentication system for gingers in order to facilitate their commercial use as genuine phytoceuticals. To this end, the objective of the present study was to develop a novel loop mediated isothermal amplification (LAMP)-based marker for authentication of the commercially important Zingiber officinale Roscoe from the closely related species. The twelve rhizome samples of these plants were collected from different geographical locations in India and analyzed with randomly amplified polymorphic DNA (RAPD). A prominent DNA fragment in RAPD that is common to all accessions was eluted, cloned and sequenced. Based on the DNA sequences four specific LAMP primers (two inner and outer primers) were in house designed for LAMP based marker. LAMP reaction was performed by using designed specific LAMP primer and total DNA extracted from Z. officinale as template. The developed LAMP-based markers were tested in several non-Zingiber species. The LAMP was observed for approximately 30 min at DNA concentrations of 10 to 15 ng. The resulting amplicon was visualized by adding SYBR Green-I to the reaction tube without using further technique as gel electrophoresis, to shorten reaction time considerably, since the assay method is simple, sensitive and rapid, for identifying and authentication of Z. officinale Roscoe.